1. Field of the Invention
The present invention relates generally to spinal fixation systems and, more particularly, to an apparatus for implementing a spinal fixation system with supplemental fixation.
2. Description of the Related Art
Spinal fixation systems typically employ a spinal rod for supporting the spine and properly positioning vertebrae of the spine for various treatment purposes. Devices such as bolts, screws, clamps and hooks are typically secured to the vertebrae for connection to the supporting spinal rod. Examples of some known spinal fixation systems are disclosed in U.S. Pat. Nos. 5,209,752 and 5,562,662.
With most spinal conditions to be corrected, surgeons can typically anticipate that the vertebral components where these devices are to be implanted or attached will normally have sufficient strength and integrity to accommodate the devices. However, this is not the typical situation surgeons face in the case of patients with osteoporotic bone conditions. Uncertainty regarding the strength of vertebrae is always present in patients with osteoporotic bone. Oftentimes one vertebral component, such as one pedicle of a plurality thereof where a particular level of fixation is planned, may have a lateral aspect that is not strong enough to hold the intended correction.
Thus, there is a need for an innovation that will compensate for this frequently encountered condition of variable vertebrae strength in order to ensure continued use of spinal fixation systems appropriate in patients with osteoporotic bone conditions.